Aerodynamic-electrostatic particulate collection system

ABSTRACT

An aerodynamic-electrostatic particulate collection system for high-efficiency collection of particulate debris generated in a machining area during machining of a workpiece, especially post-cure machining of a composite workpeice, that includes a vacuum subsystem for generating a localized, vacuum-induced aerodynamic fluid flow field in the machining area and a particulate charging, electric field generating subsystem integrated in combination with the workpiece and the vacuum subsystem for charging particulate debris generated during machining of the workpiece and for creating an electric field that directs the charged particulate debris into the localized, vacuum-induced aerodynamic fluid flow field. The vacuum subsystem includes a vacuum pump, a hose fluidically interconnected to the vacuum pump, and a nozzle fluidically connected to the hose distal the vacuum pump and having a configuration that defines the localized, vacuum-induced aerodynamic fluid flow field. The particulate charging, electric field generating subsystem includes a high voltage power supply, a first conductive lead electrically interconnecting the high voltage power supply and the workpiece, a collection electrode physically integrated in combination with the nozzle, and a second conductive lead electrically interconnecting the high voltage power supply and the collection electrode. The oppositely charged workpiece and collection electrode in combination produce a corona discharge in the machining area that causes the particulate debris generated during machining of the workpiece to be charged. Further, the oppositely charged workpiece and collection electrode in combination create the electric field that is collinear with the localized, vacuum-induced aerodynamic fluid flow field.

RELATED APPLICATION

The instant application is a divisional application of U.S. patentapplication Ser. No. 08/407,748, filed 21 Mar. 1995, entitledAERODYNAMIC-ELECTROSTATIC PARTICULATE COLLECTION SYSTEM.

TECHNICAL FIELD

The present invention relates to particulate collection systems, andmore particularly, to an aerodynamic-electrostatic particulatecollection system that utilizes aerodynamic and electrostatic forces incombination to efficaciously collect particulate debris generated duringthe machining of articles, particularly composite articles.

BACKGROUND OF THE INVENTION

The widespread utilization of composite materials such as graphite andKEVLAR® (KEVLAR is a registered trademark of E.I. du Pont de Nemours &Co., Wilmington, Del. for an aromatic polyamide fiber of high tensilestrength) embedded in a resinous matrix, e.g., epoxy, has becomecommonplace in the aerospace industry due to the high strength-to-weightratio of such composite materials. Even though composite materials areformed into composite articles in the main by various molding processes,e.g., resin transfer molding, vacuum bag molding using prepreg compositematerials, composite articles are generally subjected to standardpost-cure machining practices such as drilling, routing, milling, and/ordiamond wheel cutting to form the composite articles to net shape and/orto prepare the composite articles for integration with other articles.

Due to the brittle nature of some of the constituents elements used toform composite materials, e.g., graphite or KEVLAR® fibers, post-curemachining of composite articles often results in the generation ofparticulate debris, e.g., relatively fine particles less than 5 micronsin size down to sub-micron sizes, i.e., dust, as well as larger fiberparticles, i.e., greater than 5 microns in size up to severalmillimeters in size. Such particulate debris raises health concerns,i.e., respiration potential, for personnel working in areas wherepost-curing machining of composite articles is being undertaken as wellconcerns vis-a-vis contamination of post-cure machining tools, bearings,spindles, control electronics associated with automated machining tools,and aircraft avionics. The problems associated with the control anddisposal of particulate debris arising from post-cure machining ofcomposite articles differs from the problems arising out of themachining of metallic articles, which are generally more ductile thancomposite materials, thereby tending to form larger-sized particulatedebris which is more readily controlled and disposed of.

Several techniques are currently used to alleviate the problems arisingas a result of the particulate debris generated during the post-curemachining of composite articles. These techniques include coolantflooding, localized vacuum dust removal, and downdraft benches/booths.

In the coolant flooding technique, a specialized liquid, typically watercontaining anti-corrosive additives, is directed at the compositearticle during the machining process to entrain the generatedparticulate debris in solution. The coolant flooding technique isadvantageous inasmuch as the coolant fluid lowers the operatingtemperature of the machining tool, thereby extending the useful lifetimeof the fool. One disadvantage of this technique is the relatively highrisk of composite article contamination. If the composite articleincludes stiffeners such as cores or foam, such stiffeners are subjectto contamination if subjected to the coolant fluid. Vacuum fixtures usedto hold the composite article during the machining process may draw thecoolant fluid into contact with porous plies comprising the compositearticle. In addition to the foregoing disadvantage, the particulatedebris solution produced as a result of the coolant flooding techniquemust be treated prior to disposal, typically by filtering using acartridge-type filter or a paper roller filter, either of which requirea high level of maintenance. Even with coolant flooding, a residual filmof particulate debris usually remains on the composite article. Thisresidue must be removed from the composite article using air pressureand absorbent materials. Finally, the coolant flooding techniqueobstructs the view of the composite article during the machining processto a degree. Overall, the coolant flooding technique is relativelycostly and inflexible.

The localized vacuum debris removal technique utilizes hoses and apickup head proximal the machine tooling or composite workpiece tocreate a localized aerodynamic fluid flow field that directs particulatedebris into the pickup head for subsequent disposal. The localizedvacuum debris removal technique does not utilize liquid coolants,thereby eliminating the possibility of workpiece contamination. Thevacuum hoses and pickup head, however, are mounted directly incombination with the machining tool, and such a mounting arrangement iscumbersome and often obstructs the operator's view of the machiningtool. Furthermore, this type of mounting arrangement may not beconducive to post-cure machining of composite articles having intricateor complex shapes. In addition, the localized vacuum debris removaltechnique is relatively inefficient over the wide size range ofparticulate debris inasmuch as the size of the hose and pickup head arelimited due to the requirement to mount these components in combinationwith the tool.

In the downdraft bench/booth technique, the workpiece to be postcuremachined is mounted in the bench/booth so that a localized aerodynamicfluid flow field is directed down over the workpiece such thatparticulate debris generated during machining is directed downwardlyaway from the workpiece. This technique is not subject to plycontamination, and does not require that attachment of bulky componentsdirectly in combination with the machining tool. The downdrafttechnique, however, is less efficient than the localized vacuum dustremoval technique such that there is a higher risk that a machineoperator will be exposed to particulate debris. Moreover, this techniqueis even less conducive than the localized vacuum dust removal techniqueto post-cure machining of composite articles having intricate or complexshapes.

The use of electrostatic technology for particle control is well knownin the prior art. Representative examples of the use of suchelectrostatic technology includes U.S. Pat. Nos. 5,215,558, 5,125,124,4,941,224, 4,715,870, 4,662,903, 4,509,958, 4,248,162, 4,147,522,4,119,415, 3,994,704, 3,915,676, 3,513,635, and 2,307,602, Japanesedocuments JP363283768, JP362097650, JP362002844, and JP360129114, SovietUnion documents SU000929224 and SU00912218, and Netherlands documentNL072006447. In general, the use of such electrostatic technology forparticle control involves the use of electrostatic collectors to removecharged dust particles from an air stream. This is accomplished bysubjecting the dust-laden air stream to an electric field to cause thedust particles therein to be charged. The charged, dust-laden air streamis then subjected to an oppositely-charged element wherein the chargeddust particles are removed from the charged, dust-laden air stream.

A need exists to provide a system for collecting particulate debrisgenerated during machining of articles, particularly post-cure machiningof composite articles that utilizes aerodynamic and electrostatic forcesin combination to provide high-efficiency collection of the particulatedebris. The system should include a means for creating a localized,vacuum-induced aerodynamic fluid flow field in the article machiningarea. The system should also include a means for charging theparticulate debris generated during machining of the article. Further,the system should include a means for creating an electric field that iscollinear with the localized, vacuum-induced aerodynamic fluid flowfield.

DISCLOSURE OF THE INVENTION

One object of the present invention is to provide anaerodynamic-electrostatic particulate collection system that utilizesaerodynamic and electrostatic forces in combination to providehigh-efficiency collection of particulate debris generated duringmachining of workpieces, especially post-cure machining of compositeworkpieces.

Another object of the present invention is to provide anaerodynamic-electrostatic particulate collection system that isoperative to create a localized, vacuum-induced aerodynamic fluid flowfield in the machining area of the workpeice being machined.

A further object of the present invention is to provide anaerodynamic-electrostatic particulate collection system that isoperative to charge the particulate debris in the machining areagenerated during the machining of the workpeice.

Yet one more object of the present invention is to provide anaerodynamic-electrostatic particulate collection system that isoperative to generate an electric field that is collinear with thelocalized, vacuum-induced aerodynamic fluid flow field such that thecharged particulate debris is directed into the localized,vacuum-induced aerodynamic fluid flow field.

These and other objects are provided by an aerodynamic-electrostaticparticulate collection (AEPC) system according to the present inventionthat is operative for high-efficiency collection of particulate debrisgenerated in a machining area during machining of an a workpiece,especially a composite workpiece. The AEPC system comprises a vacuumsubsystem that is operative to generate a localized, vacuum-inducedaerodynamic fluid flow field in the machining area and a particulatecharging, electric field generating subsystem integrated in combinationwith the workpiece and the vacuum subsystem for charging particulatedebris generated during machining of the workpiece and for creating anelectric field that directs the charged particulate debris into thelocalized, vacuum-induced aerodynamic fluid flow field.

The vacuum subsystem includes a vacuum pump, a hose fluidicallyinterconnected to the vacuum pump, and a nozzle fluidically connected tothe hose distal the vacuum pump. The nozzle is positioned with respectto the workpiece and has a configuration that defines the localized,vacuum-induced aerodynamic fluid flow field.

The particulate charging, electric field generating subsystem includes ahigh voltage power supply, a first conductive lead electricallyinterconnecting the high voltage power supply and the workpiece, acollection electrode physically integrated in combination with thenozzle, and a second conductive lead electrically interconnecting thehigh voltage power supply and the collection electrode. The oppositelycharged workpiece and collection electrode in combination produce acorona discharge in the machining area that causes the particulatedebris generated during machining of the workpiece to be charged.Further, the oppositely charged workpiece and collection electrode incombination create the electric field that is collinear with thelocalized, vacuum-induced aerodynamic fluid flow field. The collinearitybetween the localized, vacuum-induced aerodynamic fluid flow field andthe electric field provides the high-efficiency collection of theaerodynamic-electrostatic particulate collection system.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention and the attendantfeatures and advantages thereof may be had by reference to the followingdetailed description when considered in conjunction with theaccompanying drawings wherein:

FIG. 1 is an exemplary embodiment of an aerodynamic-electrostaticparticulate collection (AEPC) system according to the present invention.

FIG. 2 is an embodiment of the AEPC system according to the presentinvention depicting a detailed perspective view of the nozzleconfiguration of the vacuum subsystem.

FIG. 2A is an exploded perspective view of the nozzle configuration ofFIG. 2.

FIG. 3 illustrates another embodiment of a nozzle configuration for theAEPC system according to the present invention.

FIG. 4 illustrates still another embodiment of a nozzle configurationfor the AEPC system according to the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION

Referring now to the drawings wherein like reference numerals identifycorresponding or similar elements throughout the several views, FIG. 1illustrates an exemplary embodiment of an aerodynamic-electrostaticparticulate collection (AEPC) system 10 according to the presentinvention. A workpiece WP to be post-cure machined is mounted on aworkbench WB by means of a fixture F and positioned for machining bymeans of a machine tool MT as illustrated, a drill for routing aperturesin the workpiece WP). As one skilled in the art will appreciate from theensuing disclosure, the AEPC system 10 according to the presentinvention has utility for post-cure machining operations involvingworkpieces WP which are conductive, and in particular, compositeconductive workpieces WP. The AEPC system 10 has particular utility forenhanced particulate debris collection during post-cure machiningoperations involving graphite or KEVLAR® composite articles, but may beused in combination with other composite articles that are conductive orwith other types of articles that are conductive.

The AEPC system 10 of the present invention utilizes electrostatic andaerodynamic-vacuum technologies in integrated combination tosignificantly improve the collection of particulate debris generatedduring post-cure machining of workpieces WP. The AEPC system 10 includesa vacuum subsystem 20 and a particulate charging, electric fieldgenerating (pc-efg) means 40. The vacuum subsystem 20 is operative togenerate a localized vacuum-induced aerodynamic fluid flow field in thevicinity of the workpiece WP machining area that removes particulatedebris generated by post-cure machining of the workpiece WP from themachining area. The pc-efg means 40 is integrated in combination withthe vacuum subsystem 20 and is operative: (i) to charge the particulatedebris emitted from the workpiece WP during post-cure machining thereof,and (ii) to create an electric field that directs the chargedparticulate debris into the localized aerodynamic fluid flow field. Theelectric force field generated by the pc-efg means 40 is utilized toenhance the particulate debris collection efficiency of the vacuumsubsystem 20, i.e., the percentage of particulate debris entrained inthe aerodynamic fluid flow field is significantly increased.

Electrostatic particulate debris collection takes place through twomechanisms: (i) corona charging of particulate debris generated duringpost-cure machining of the workpiece WP; and (ii) electric fieldtransport of the charged particulate debris. The particulate debrisgenerated as a result of workpiece WP machining operations is charged asa result of the free electrons produced in the electric corona generatedby the pc-efg means 40. The strong electric field strips away electronsfrom gas molecules, leaving positive gas ions, which migrate from thecorona region. Particulate debris in the vicinity of the workpiece WP ischarged by the free electrons. The electric field developed by thepc-efg means 40 directs the charged particulate debris into thelocalized aerodynamic fluid flow field generated by the vacuum subsystem20. The electrostatic forces acting on the particulate debris arefunctions of the particulate size, mass, strength of the collectionfield, and residence time in the corona region.

The vacuum subsystem 20 includes a vacuum pump 22, a hose 24, a nozzle26 at the end of the hose 24 distal the vacuum pump 22, and a filtrationdevice 28 integrated in combination with the vacuum subsystem 20 (withthe hose 24 in the illustrated embodiment, or alternatively, with thevacuum pump 22). The nozzle 26 is configured: (i) to develop thelocalized vacuum-induced aerodynamic fluid flow field in the machiningarea immediately adjacent the workpiece WP; and (ii) to facilitatemounting of the electrode of the pc-efg means (40) in combinationtherewith (see specific embodiments described hereinbelow). In addition,for operator-wielded machining tools, the nozzle 26 is configured: (i)for mounting in combination with the machining tool; and (ii) tominimize the visual obstructive effects thereof so that the workpiece WPis readily visible to the operator during post-cure machiningoperations. These latter design criteria may or may not be required forNC or automated machining tools. The filtration device 28 is any of thefiltration mechanisms conventionally used to remove particulate debrisfrom a gaseous fluid flow field system and is operative to removeparticulate debris entrained in the aerodynamic fluid flow fieldtransmitted through the vacuum subsystem 20, thereby ensuring that theoperation of the vacuum pump 22 is not degraded due to the ingestion ofparticulate debris.

The pc-efg means 40 comprises a high voltage power supply 42, a firstconductive lead 44, a second conductive lead 46, a collection electrode48, and a current interrupter device 50. The high voltage power supply42 is any conventional high energy D.C. power supply that is operativeto produce a high voltage (e.g., a range of about 12 kV to about 20 kV)at very low amperes (e.g., a range of about 400 microamps to about 1800microamps). The first conductive lead 44 electrically interconnects thehigh voltage power supply 42 to the workpiece WP. The collectionelectrode 48 is integrated in combination with the nozzle 26 adjacentthe inlet 261 thereof. The collection electrode 48 may be mounted as aseparate element in combination with the nozzle inlet 261 (asillustrated in FIGS. 1 or 3) or may be fabricated as pad of thestructure defining the nozzle inlet 261 (see FIGS. 2 or 4). The secondconductive lead 46 electrically interconnects the high voltage powersupply 42 to the collection electrode 48.

With the high voltage power supply 42 activated, the oppositely chargedworkpiece WP and collection electrode 48 in combination produce a coronadischarge in the machining area that causes the particulate debrisgenerated during post-cure machining of the workpiece WP to becomenegatively charged. Concomitantly, the oppositely charged workpiece WPand the collection electrode 48 in combination create an electric forcefield therebetween that causes the negatively charged particulate debristo be transported towards the collection electrode 48.

Since the collection electrode 48 is integrated in combination with thenozzle inlet 261, the electric force field generated by the pc-efg means40 is collinear with the aerodynamic fluid flow field generated by thevacuum subsystem 20. The collinearity of the electric and aerodynamicfields generated by the AEPC system 10 according to the presentinvention significantly enhances the particulate debris collectionefficiency thereof.

The workpiece WP should be electrically interconnected to the highvoltage power supply 42 so as to be at ground potential. This precludesany arcing between the workpiece WP and the machining tool MT duringpost-cure machining operations. The current interrupter device 50 (shownin FIG. 1 as mounted in combination with the second conductive lead 46)is operative to momentarily de-energize the collection electrode 48during operation of the AEPC system 10. During operation of the AEPCsystem 10, negatively charged particulate debris is electrostaticallyattracted to and accumulates on the collection electrode 48. Anexcessive accumulation of negatively charged particulate debris on thecollection electrode 48 impairs the collection efficiency of the AEPCsystem 10 by weakening the electric force field and obstructing theaerodynamic fluid flow field into the nozzle 26. Operation of thecurrent interrupter device 50 momentarily negates the electrostaticattraction force exerted by the collection electrode 48 so that thecharged particulate debris that has electrostatically accumulated on thecollection electrode 48 can be effectively dislodged therefrom by theaerodynamic fluid flow field through the inlet 261 of the nozzle 26 andtransmitted through the hose 24 to the filtration device 28. Thefrequency of de-energization is such as to ensure that the efficiency ofthe collection electrode 48 is not markedly affected by the build-up ofnegatively charged particle debris electrostatically collected on thecollection electrode 48. The interrupter means 50 may be anyconventional circuit or device that performs the described function.

FIGS. 2, 2A illustrate one embodiment of a nozzle 26A for the vacuumsubsystem 20 of the AEPC system 10 according to the present invention.The nozzle 26A is configured for mounting in combination with ahand-held machine tool MT (as illustrated, a router that includes a bitB_(MT) for machining apertures, etc., in the workpiece WP). The nozzle26A includes a nozzle body 30 and a plate 34 mounted in rotatablecombination with the nozzle body 30. The nozzle body 30 has acylindrical configuration that defines an internal channel 31 andincludes an apertured attachment flange 32 and an extension member 33.The internal channel 31 has a tapered configuration (see FIG. 2) thatfacilitates development of the localized vacuum-induced aerodynamicfluid flow field in the machining area of the workpiece WP. Theapertured attachment flange 32 is operative for mounting the nozzle 26Ain combination with the machine tool MT by means of the aperture 32atherethrough. The extension member 33 is operative to fiuidicallyinterconnect the nozzle 26A to the hose 24 (note that part of the hose24 is formed as a handle 24H for operator convenience). As illustratedin FIG. 2A, the second conductive wire 46 is routed through theextension member 33 (and the vacuum hose 24) for safety.

The plate 34 includes a central aperture 35, first and second arcuateapertures 36a, 36b, and first and second duct aperture 37a, 37b. A pairof ducts 38a, 38b, which are in fluidic communication with the first andsecond duct apertures 37a, 37b, respectively, extend downwardly from theplate 34. In this embodiment of the nozzle 26A, the collection electrode48A is part of the structure defining the ducts 38a, 38b. Morespecifically, the collection electrode 48A is formed by plating aconductive material, e.g., copper, onto the internal surfaces of thewalls defining the ducts 38a, 38b. The second conductive lead 46 iselectrically interconnected to the collection electrode 48A.

The internal channel 31, the aperture 32a, and the central aperture 35of the nozzle 26A in combination allow the bit B_(MT) to extend throughthe nozzle 26A for interaction with the workpiece WP. The ducts 38a, 38bextend downwardly proximal the bit B_(MT) while allowing sufficientclearance for the bit B_(MT) to penetrate the workpiece WP. Theconfiguration of the ducts 38a, 38b define the nozzle inlet for thenozzle 26A which creates the primary vacuum-induced aerodynamic fluidflow field in the machining area adjacent the workpiece WP, this primaryaerodynamic fluid flow field being collinear with the electric fieldgenerated between the workpiece WP and the collection electrode 48A. Thefirst and second arcuate apertures 36a, 36b create a secondaryvacuum-induced fluid flow field in the machining area. The aerodynamicfluid flow field through the ducts 38a, 38b and the apertures 36a, 36b,37a, 37b causes the plate 34 to rotate (see arrow R-R in FIG. 2A) withrespect to the body member 30. Rotational motion of the plate 34provides the added benefit that the collinear electric and aerodynamicfluid flow field fields sweep over the entire machining area, therebysignificantly enhancing the collection efficiency of the AEPC system 10.

Other exemplary nozzle configurations are illustrated in FIGS. 3, 4.FIG. 3 illustrates a removable shroud nozzle 26B configured for use incombination with hand-held machine tools MT such as drills, routers,milling tools, and cutting tools. The shroud nozzle 26B has a taperedconfiguration that is sized to fit onto the end of the machine tool MT(the shroud nozzle 26B may be removably held in place by anyconventional mechanism such as a clamp CI). The shroud nozzle 26B isfiuidically coupled to the vacuum pump by means of the hose as describedhereinabove. The collection electrode 48B for the shroud nozzle 26B is awire having a spiral or helical configuration that is internally mountedat the inlet end of the shroud nozzle 26B. The shroud nozzle 26B ispreferably fabricated from a rigid plastic material that is transparentto provide the operator with a relatively unobstructed view of theworkpiece WP machining area.

FIG. 4 illustrates a collection cup nozzle 26C configured for use incombination with hand-held machine tools MT such as drills, routers,milling tools, and cutting tools having an extended bit B_(MT). Thecollection cup nozzle 26C is configured to be overlayed on fop of theworkpiece WP. The collection nozzle 26C has a closed-ended cylindricalconfiguration that includes a first aperture 52b formed through oneclosed end thereof and a second aperture 52a formed through the otherclosed end thereof. The second aperture 52a is sized to allow theextended bit B_(MT) to protrude therethrough to engage the workpiece WP.The collection cup nozzle 26C is fluidically coupled to the vacuum pumpby means of the hose 24 as illustrated. The collection electrode 48C forthe collection cup nozzle 26C is an annular plate that defines the firstaperture 52b of the collection cup nozzle 26C. The collection cup nozzle26C is preferably fabricated from a rigid plastic material that istransparent to provide the operator with a relatively unobstructed viewof the workpiece WP machining area.

A variety of modifications and variations of the present invention arepossible in light of the above teachings. It is therefore to beunderstood that, within the scope of the appended claims, the presentinvention may be practiced otherwise than as specifically describedhereinabove.

What is claimed is:
 1. An aerodynamic-electrostatic particulatecollection system for high-efficiency collection of particulate debrisgenerated in a machining area during machining of a workpiece,comprising:a vacuum subsystem for generating a localized, vacuum-inducedaerodynamic fluid flow field in the machining area during operation ofsaid aerodynamic-electrostatic particulate collection system, saidvacuum subsystem includinga vacuum pump, a hose fluidically connected tosaid vacuum pump, and a nozzle fluidically connected to said hose distalsaid vacuum pump, said nozzle having a tapered configuration defining anattachment end and an inlet end and including means for removablyattaching said nozzle by said attachment end in combination with amachine tool, and said nozzle being positioned with respect to theworkpiece wherein said tapered configuration of said nozzle develops thelocalized, vacuum-induced aerodynamic fluid flow field in the machiningarea; and particulate charging, electric field generating meansintegrated in combination with the workpiece and said vacuum subsystemfor charging particulate debris generated during machining of theworkpiece and for creating an electric field between the workpiece andsaid nozzle that directs the charged particulate debris into thelocalized, vacuum-induced aerodynamic fluid flow field during operationof said aerodynamic-electrostatic particulate collection system, saidparticulate charging, electric field generating means includinga highvoltage power supply, a first conductive lead electricallyinterconnecting said high voltage power supply and the workpiece, acollection electrode in the form of a spiral wire physically integratedin combination with said inlet end of said nozzle, and a secondconductive lead electrically interconnecting said high voltage powersupply and said collection electrode; the oppositely charged workpieceand said collection electrode in combination producing a coronadischarge in the machining area that causes the particulate debrisgenerated during machining of the workpiece to become charged; theoppositely charged workpiece and said collection electrode incombination creating the electric field between the workpiece and saidnozzle that is collinear with the localized, vacuum-induced aerodynamicfluid flow field.
 2. An aerodynamic-electrostatic particulate collectionsystem for high-efficiency collection of particulate debris generated ina machining area during machining of a workpiece, comprising:a vacuumsubsystem for generating a localized, vacuum-induced aerodynamic fluidflow field in the machining area during operation of saidaerodynamic-electrostatic particulate collection system, said vacuumsubsystem includinga vacuum pump, a hose fluidically connected to saidvacuum pump, and a nozzle fluidically connected to said hose distal saidvacuum pump, said nozzle having a closed-end cylindrical configurationwherein each closed-end has an aperture formed therethrough, and saidnozzle being positioned with respect to the workpiece wherein saidclosed-end cylindrical configuration of said nozzle develops thelocalized, vacuum-induced aerodynamic fluid flow field in the machiningarea; and particulate charging, electric field generating meansintegrated in combination with the workpiece and said vacuum subsystemfor charging particulate debris generated during machining of theworkpiece and for creating an electric field between the workpiece andsaid nozzle that directs the charged particulate debris into thelocalized, vacuum-induced aerodynamic fluid flow field during operationof said aerodynamic-electrostatic particulate collection system, saidparticulate charging, electric field generating means includinga highvoltage power supply, a first conductive lead electricallyinterconnecting said high voltage power supply and the workpiece, acollection electrode in the form of an annular conductive member bondedin combination with one said closed-end aperture of said nozzle, and asecond conductive lead electrically interconnecting said high voltagepower supply and said collection electrode; the oppositely chargedworkpiece and said collection electrode in combination producing acorona discharge in the machining area that causes the particulatedebris generated during machining of the workpiece to become charged;the oppositely charged workpiece and said collection electrode incombination creating the electric field between the workpiece and saidnozzle that is collinear with the localized, vacuum-induced aerodynamicfluid flow field.